2009 temperatures by Jim Hansen

This is Hansen et al’s end of year summary for 2009 (with a couple of minor edits). Update: A final version of this text is available here.

If It’s That Warm, How Come It’s So Damned Cold?

by James Hansen, Reto Ruedy, Makiko Sato, and Ken Lo

The past year, 2009, tied as the second warmest year in the 130 years of global instrumental temperature records, in the surface temperature analysis of the NASA Goddard Institute for Space Studies (GISS). The Southern Hemisphere set a record as the warmest year for that half of the world. Global mean temperature, as shown in Figure 1a, was 0.57°C (1.0°F) warmer than climatology (the 1951-1980 base period). Southern Hemisphere mean temperature, as shown in Figure 1b, was 0.49°C (0.88°F) warmer than in the period of climatology.

The global record warm year, in the period of near-global instrumental measurements (since the late 1800s), was 2005. Sometimes it is asserted that 1998 was the warmest year. The origin of this confusion is discussed below. There is a high degree of interannual (year‐to‐year) and decadal variability in both global and hemispheric temperatures. Underlying this variability, however, is a long‐term warming trend that has become strong and persistent over the past three decades. The long‐term trends are more apparent when temperature is averaged over several years. The 60‐month (5‐year) and 132 month (11‐year) running mean temperatures are shown in Figure 2 for the globe and the hemispheres. The 5‐year mean is sufficient to reduce the effect of the El Niño – La Niña cycles of tropical climate. The 11‐year mean minimizes the effect of solar variability – the brightness of the sun varies by a measurable amount over the sunspot cycle, which is typically of 10‐12 year duration.

There is a contradiction between the observed continued warming trend and popular perceptions about climate trends. Frequent statements include: “There has been global cooling over the past decade.” “Global warming stopped in 1998.” “1998 is the warmest year in the record.” Such statements have been repeated so often that most of the public seems to accept them as being true. However, based on our data, such statements are not correct. The origin of this contradiction probably lies in part in differences between the GISS and HadCRUT temperature analyses (HadCRUT is the joint Hadley Centre/University of East Anglia Climatic Research Unit temperature analysis). Indeed, HadCRUT finds 1998 to be the warmest year in their record. In addition, popular belief that the world is cooling is reinforced by cold weather anomalies in the United States in the summer of 2009 and cold anomalies in much of the Northern Hemisphere in December 2009. Here we first show the main reason for the difference between the GISS and HadCRUT analyses. Then we examine the 2009 regional temperature anomalies in the context of global temperatures.

Figure 3. Temperature anomalies in 1998 (left column) and 2005 (right column). Top row is GISS analysis, middle row is HadCRUT analysis, and bottom row is the GISS analysis masked to the same area and resolution as the HadCRUT analysis. [Base period is 1961‐1990.]

Figure 3 shows maps of GISS and HadCRUT 1998 and 2005 temperature anomalies relative to base period 1961‐1990 (the base period used by HadCRUT). The temperature anomalies are at a 5 degree‐by‐5 degree resolution for the GISS data to match that in the HadCRUT analysis. In the lower two maps we display the GISS data masked to the same area and resolution as the HadCRUT analysis. The “masked” GISS data let us quantify the extent to which the difference between the GISS and HadCRUT analyses is due to the data interpolation and extrapolation that occurs in the GISS analysis. The GISS analysis assigns a temperature anomaly to many gridboxes that do not contain measurement data, specifically all gridboxes located within 1200 km of one or more stations that do have defined temperature anomalies.

The rationale for this aspect of the GISS analysis is based on the fact that temperature anomaly patterns tend to be large scale. For example, if it is an unusually cold winter in New York, it is probably unusually cold in Philadelphia too. This fact suggests that it may be better to assign a temperature anomaly based on the nearest stations for a gridbox that contains no observing stations, rather than excluding that gridbox from the global analysis. Tests of this assumption are described in our papers referenced below.

Figure 4. Global surface temperature anomalies relative to 1961‐1990 base period for three cases: HadCRUT, GISS, and GISS anomalies limited to the HadCRUT area. [To obtain consistent time series for the HadCRUT and GISS global means, monthly results were averaged over regions with defined temperature anomalies within four latitude zones (90N‐25N, 25N‐Equator, Equator‐25S, 25S‐90S); the global average then weights these zones by the true area of the full zones, and the annual means are based on those monthly global means.]

Figure 4 shows time series of global temperature for the GISS and HadCRUT analyses, as well as for the GISS analysis masked to the HadCRUT data region. This figure reveals that the differences that have developed between the GISS and HadCRUT global temperatures during the past few decades are due primarily to the extension of the GISS analysis into regions that are excluded from the HadCRUT analysis. The GISS and HadCRUT results are similar during this period, when the analyses are limited to exactly the same area. The GISS analysis also finds 1998 as the warmest year, if analysis is limited to the masked area. The question then becomes: how valid are the extrapolations and interpolation in the GISS analysis? If the temperature anomaly scale is adjusted such that the global mean anomaly is zero, the patterns of warm and cool regions have realistic‐looking meteorological patterns, providing qualitative support for the data extensions. However, we would like a quantitative measure of the uncertainty in our estimate of the global temperature anomaly caused by the fact that the spatial distribution of measurements is incomplete. One way to estimate that uncertainty, or possible error, can be obtained via use of the complete time series of global surface temperature data generated by a global climate model that has been demonstrated to have realistic spatial and temporal variability of surface temperature. We can sample this data set at only the locations where measurement stations exist, use this sub‐sample of data to estimate global temperature change with the GISS analysis method, and compare the result with the “perfect” knowledge of global temperature provided by the data at all gridpoints.

Table 1 shows the derived error due to incomplete coverage of stations. As expected, the error was larger at early dates when station coverage was poorer. Also the error is much larger when data are available only from meteorological stations, without ship or satellite measurements for ocean areas. In recent decades the 2‐sigma uncertainty (95 percent confidence of being within that range, ~2‐3 percent chance of being outside that range in a specific direction) has been about 0.05°C. The incomplete coverage of stations is the primary cause of uncertainty in comparing nearby years, for which the effect of more systematic errors such as urban warming is small.

Additional sources of error become important when comparing temperature anomalies separated by longer periods. The most well‐known source of long‐term error is “urban warming”, human‐made local warming caused by energy use and alterations of the natural environment. Various other errors affecting the estimates of long‐term temperature change are described comprehensively in a large number of papers by Tom Karl and his associates at the NOAA National Climate Data Center. The GISS temperature analysis corrects for urban effects by adjusting the long‐term trends of urban stations to be consistent with the trends at nearby rural stations, with urban locations identified either by population or satellite‐observed night lights. In a paper in preparation we demonstrate that the population and night light approaches yield similar results on global average. The additional error caused by factors other than incomplete spatial coverage is estimated to be of the order of 0.1°C on time scales of several decades to a century, this estimate necessarily being partly subjective. The estimated total uncertainty in global mean temperature anomaly with land and ocean data included thus is similar to the error estimate in the first line of Table 1, i.e., the error due to limited spatial coverage when only meteorological stations are included.

Now let’s consider whether we can specify a rank among the recent global annual temperatures, i.e., which year is warmest, second warmest, etc. Figure 1a shows 2009 as the second warmest year, but it is so close to 1998, 2002, 2003, 2006, and 2007 that we must declare these years as being in a virtual tie as the second warmest year. The maximum difference among these in the GISS analysis is ~0.03°C (2009 being the warmest among those years and 2006 the coolest). This range is approximately equal to our 1‐sigma uncertainty of ~0.025°C, which is the reason for stating that these five years are tied for second warmest.

The year 2005 is 0.061°C warmer than 1998 in our analysis. So how certain are we that 2005 was warmer than 1998? Given the standard deviation of ~0.025°C for the estimated error, we can estimate the probability that 1998 was warmer than 2005 as follows. The chance that 1998 is 0.025°C warmer than our estimated value is about (1 – 0.68)/2 = 0.16. The chance that 2005 is 0.025°C cooler than our estimate is also 0.16. The probability of both of these is ~0.03 (3 percent). Integrating over the tail of the distribution and accounting for the 2005‐1998 temperature difference being 0.61°C alters the estimate in opposite directions. For the moment let us just say that the chance that 1998 is warmer than 2005, given our temperature analysis, is at most no more than about 10 percent. Therefore, we can say with a reasonable degree of confidence that 2005 is the warmest year in the period of instrumental data.

Figure 5. (a) global map of December 2009 anomaly, (b) global map of Jun‐Jul‐Aug 2009 anomaly. #4 and #2 indicate that December 2009 and JJA are the 4th and 2nd warmest globally for those periods.

What about the claim that the Earth’s surface has been cooling over the past decade? That issue can be addressed with a far higher degree of confidence, because the error due to incomplete spatial coverage of measurements becomes much smaller when averaged over several years. The 2‐sigma error in the 5‐year running‐mean temperature anomaly shown in Figure 2, is about a factor of two smaller than the annual mean uncertainty, thus 0.02‐0.03°C. Given that the change of 5‐year‐mean global temperature anomaly is about 0.2°C over the past decade, we can conclude that the world has become warmer over the past decade, not cooler.

Why are some people so readily convinced of a false conclusion, that the world is really experiencing a cooling trend? That gullibility probably has a lot to do with regional short‐term temperature fluctuations, which are an order of magnitude larger than global average annual anomalies. Yet many lay people do understand the distinction between regional short‐term anomalies and global trends. For example, here is comment posted by “frogbandit” at 8:38p.m. 1/6/2010 on City Bright blog:

“I wonder about the people who use cold weather to say that the globe is cooling. It forgets that global warming has a global component and that its a trend, not an everyday thing. I hear people down in the lower 48 say its really cold this winter. That ain’t true so far up here in Alaska. Bethel, Alaska, had a brown Christmas. Here in Anchorage, the temperature today is 31[ºF]. I can’t say based on the fact Anchorage and Bethel are warm so far this winter that we have global warming. That would be a really dumb argument to think my weather pattern is being experienced even in the rest of the United States, much less globally.”

What frogbandit is saying is illustrated by the global map of temperature anomalies in December 2009 (Figure 5a). There were strong negative temperature anomalies at middle latitudes in the Northern Hemisphere, as great as ‐8°C in Siberia, averaged over the month. But the temperature anomaly in the Arctic was as great as +7°C. The cold December perhaps reaffirmed an impression gained by Americans from the unusually cool 2009 summer. There was a large region in the United States and Canada in June‐July‐August with a negative temperature anomaly greater than 1°C, the largest negative anomaly on the planet.

Figure 6. Arctic Oscillation (AO) Index. Positive values of the AO index indicate high low pressure in the polar region and thus a tendency for strong zonal winds that minimize cold air outbreaks to middle latitudes. Blue dots are monthly means and the red curve is the 60‐month (5‐year) running mean.

How do these large regional temperature anomalies stack up against an expectation of, and the reality of, global warming? How unusual are these regional negative fluctuations? Do they have any relationship to global warming? Do they contradict global warming?

It is obvious that in December 2009 there was an unusual exchange of polar and mid‐latitude air in the Northern Hemisphere. Arctic air rushed into both North America and Eurasia, and, of course, it was replaced in the polar region by air from middle latitudes. The degree to which Arctic air penetrates into middle latitudes is related to the Arctic Oscillation (AO) index, which is defined by surface atmospheric pressure patterns and is plotted in Figure 6. When the AO index is positive surface pressure is high low in the polar region. This helps the middle latitude jet stream to blow strongly and consistently from west to east, thus keeping cold Arctic air locked in the polar region. When the AO index is negative there tends to be low high pressure in the polar region, weaker zonal winds, and greater movement of frigid polar air into middle latitudes.

Figure 6 shows that December 2009 was the most extreme negative Arctic Oscillation since the 1970s. Although there were ten cases between the early 1960s and mid 1980s with an AO index more extreme than ‐2.5, there were no such extreme cases since then until last month. It is no wonder that the public has become accustomed to the absence of extreme blasts of cold air.

Figure 7. Temperature anomaly from GISS analysis and AO index from NOAA National Weather Service Climate Prediction Center. United States mean refers to the 48 contiguous states.

Figure 7 shows the AO index with greater temporal resolution for two 5‐year periods. It is obvious that there is a high degree of correlation of the AO index with temperature in the United States, with any possible lag between index and temperature anomaly less than the monthly temporal resolution. Large negative anomalies, when they occur, are usually in a winter month. Note that the January 1977 temperature anomaly, mainly located in the Eastern United States, was considerably stronger than the December 2009 anomaly. [There is nothing magic about a 31 day window that coincides with a calendar month, and it could be misleading. It may be more informative to look at a 30‐day running mean and at the Dec‐Jan‐Feb means for the AO index and temperature anomalies.]

The AO index is not so much an explanation for climate anomaly patterns as it is a simple statement of the situation. However, John (Mike) Wallace and colleagues have been able to use the AO description to aid consideration of how the patterns may change as greenhouse gases increase. A number of papers, by Wallace, David Thompson, and others, as well as by Drew Shindell and others at GISS, have pointed out that increasing carbon dioxide causes the stratosphere to cool, in turn causing on average a stronger jet stream and thus a tendency for a more positive Arctic Oscillation. Overall, Figure 6 shows a tendency in the expected sense. The AO is not the only factor that might alter the frequency of Arctic cold air outbreaks. For example, what is the effect of reduced Arctic sea ice on weather patterns? There is not enough empirical evidence since the rapid ice melt of 2007. We conclude only that December 2009 was a highly anomalous month and that its unusual AO can be described as the “cause” of the extreme December weather.

We do not find a basis for expecting frequent repeat occurrences. On the contrary. Figure 6 does show that month‐to‐month fluctuations of the AO are much larger than its long term trend. But temperature change can be caused by greenhouse gases and global warming independent of Arctic Oscillation dynamical effects.

Figure 8. Global maps 4 season temperature anomalies for ~2009. (Note that Dec is December 2008. Base period is 1951‐1980.)

So let’s look at recent regional temperature anomalies and temperature trends. Figure 8 shows seasonal temperature anomalies for the past year and Figure 9 shows seasonal temperature change since 1950 based on local linear trends. The temperature scales are identical in Figures 8 and 9. The outstanding characteristic in comparing these two figures is that the magnitude of the 60 year change is similar to the magnitude of seasonal anomalies. What this is telling us is that the climate dice are already strongly loaded. The perceptive person who has been around since the 1950s should be able to notice that seasonal mean temperatures are usually greater than they were in the 1950s, although there are still occasional cold seasons.

The magnitude of monthly temperature anomalies is typically 1.5 to 2 times greater than the magnitude of seasonal anomalies. So it is not yet quite so easy to see global warming if one’s figure of merit is monthly mean temperature. And, of course, daily weather fluctuations are much larger than the impact of the global warming trend. The bottom line is this: there is no global cooling trend. For the time being, until humanity brings its greenhouse gas emissions under control, we can expect each decade to be warmer than the preceding one. Weather fluctuations certainly exceed local temperature changes over the past half century. But the perceptive person should be able to see that climate is warming on decadal time scales.

This information needs to be combined with the conclusion that global warming of 1‐2°C has enormous implications for humanity. But that discussion is beyond the scope of this note.

932 Responses to “2009 temperatures by Jim Hansen”

Let me correct that: The science in IPCC is first rate. The solutions business side of IPCC and Copenhagen and so forth is a complete [edit]

[Response: The IPCC had/has nothing to do with Copenhagen. Policies may be ineffectual, or incoherent or produce the opposite of what is intended – but whatever it is you wish to convey, I suggest you use more appropriate language. – gavin]

Ron: “As a follow up to my comment about China, in spite of their refusal to commit to reduction targets, ”

Except they did.

They stated that they would reduce CO2 per GDP. Since they make most of the western world’s heavy goods and being cheaper (and without those pesky labour laws that stop people being protected at work at the expense of their shareholder’s Beemer), they didn’t want the west dumping more on them and making China work twice as hard where they have now exported all their CO2 and can happily drive 10 litre hummers.

All that was needed to ensure a real *absolute* reduction was to buy less from China.

I appreciate, greatly, your effort to see my comments in a true light, as free of preconceived bias as possible. Would it only be that others would see the benefit of that effort.

Eventually they will, but the majority of the gang in here serves as a proxy for the larger reality: They don’t want to know.

And because they don’t want to know, guess what? They remain human pinballs, caught between advocates arguing about the science and dug-in politicians and their proxies, who are viciously determined to defend their turf, even at the expense of lying through their teeth.

Acceleration is real, folks.

If we stopped emitting CO2 TODAY, (a) CO2 would continue to rise from natural sources, a process which is accelerating and (b) the chemistry between the atmosphere and the top layer of the world ocean will see to it that levels do not sink in any period of time which matters to this discussion.

Yes, Dr. Hansen may be able to envision an eventual stabilization at 350 ppm, but then he would have to address what the world will look like when that day comes, many many decades from now.

That world will be much more heavily influenced by its own momentum than by anything that man can do.

I know that Dr. Hansen knows that, but for whatever reason, he doesn’t mention it when discussing his reduction scenarios.

An honest statement in that regard would sound something like this:

“We can, through certain measures, reduce atmospheric CO2 over time. However, the planet will continue to warm for some period after that, and changes already underway will have to essentially complete before they can reverse, because of the enormous amounts of energy involved. Therefore, we will lose a lot of ice mass, we can’t say how much, and nations will need to address such consequences. It would benefit them to start soon.”

See how that shifts the focus?

Does that help explain why nobody’s saying it? That view currently fits no popular agenda. It does not fit the denier agenda – what, admit that the planet is warming?, nor does it fit the warmist agenda – what, admit that we can’t stop it?

See, I am focused on two things: 1) CO2 emissions and 2) acceleration.

See the years you mentioned? 2030, 2050? If I am correct that we are already past the point of no return, then those years are far, far too late.

See above. I assert that acceleration is already unstoppable. I am looking for the specific reference, but I read last night that the scientist for the IPY project to analyze the Greenland ice sheet has determined that it is already lost.

We have no idea about the time scales, of course, not today, and certainly a warmer planet will speed the acceleration, so we should do what we can to limit that warming. No argument.

When I say “the needle hasn’t moved” I mean in the area where it matters: A global agreement to reduce CO2 emissions.

Suppose I’m wrong about the point of no return. How wrong am I? Ten years at most?

Even you don’t predict that we will be reducing CO2 emissions in ten years.

Jim (Dr. Hansen) objects to me calling this a game, perhaps because he believes that it connotes something less than serious.

If Jim cares about understanding my position, then he will have read enough of my posts to know that I am far from frivolous in my views. Completely out of step? Yes, today. But guess what? I am getting much more traction here these days than I did a year ago with essentially the same observations.

Why? Well for one thing, Copnhagen came and went without a binding agreement (Good!) and for another, at least some among you are trying to stay rational and not just pick a leader to follow, no matter what they say.

My two biggest heroes are Gore and Hansen, and look what’s become of them: Gore supports a fraudulent bill, and Dr. Hansen runs from his own empirical conclusions.

WB: CO2 emissions, for the next couple of decades, will continue to increase… Somewhere in there it will flatten. Ten years? Maybe. Nothing has happened as fast as we would like, so my hedge is that it’s more like 20.

You cannot deny that IPCC has a political slant (leftward, obviously), as do the people who are trying to sell us on global treaties.

I really don’t know how we can separate them. Would there be climate policy groups without the IPCC findings?

And Gavin, I appreciate the couched language you use. See, I honestly pity you and others in the climate science world. I’m sure an anonymous poll would reveal a strong bias toward the opinion that we have passed the point of destabilization, throwing us into a wild new era of unknowns. I understand the enormous pressure you’re under to keep seeking “solution”. It’s far too political now, and that will only get worse.

Let me ask you a question: Have models been run to identify a destabilization point? Can the question even be framed as something that can be modeled?

[Response: I do it to prevent conversations taking pointless detours (like this one) about language and tone. This is our forum, run our way. If you want something different, host it yourself. This is not up for discussion. – gavin]

I was referring to the natural acceleration of a warming event. Dr. Hansen, for one, believes that we reach a point in a warming where the event must complete itself, in other words, little or no permanent ice.

Exactly what is it that dams form behind them? Virtually everything is dammed and has reservoirs already. You have vast holes in your knowledge of current conditions. You may want to slow down before claiming to know what is to be done as long as it avoids taxes and real solutions.

I’m quite happy to have any of my suggestions improved upon, which would at a minimum require the other person to present me with some information.

With regard to reservoirs, I don’t know why you consider it necessary to associate dams with reservoirs. As you surely know, there are many reservoirs which are not the result of dams.

I never meant to use the word dams at all. It was a complete mistake, an accident.

This is the third time I am saying this and I don’t like to waste everybody’s time doing that, so for the last time:

The U.S. of the future will have less snow but more rain, and snow/glacier-based rivers will run low or run dry. Wet and dry regions will likely also shift, and the wet regions will likely get far more rainfall than they could, today, capture and preserve. Thus, in order to survive in that new world, we need a comprehensive national water management strategy which at a minimum improves on how much rainwater can be captured and preserved but which should also include dumping as little waste water as possible into streams and back out to sea (better to recycle and preserve it) as well as an integrated network to get water from where it falls to where its needed, and to replenish low supplies from over-supplied stocks.

Now, can I make an easy million by betting that much that not you nor Hank nor anybody else can produce evidence that there is even a concerted effort to have that discussion, let alone actually taking steps in that direction?

CFU, I’m not sure why you conclude from your link that China feels it does not need to burn fossil fuels. It clearly recognizes that the future is in non-fossil energy sources, but it will burn fossil fuels during the transition of its energy system to the extent necessary to maintain civil order. That is a non-negotiable commitment of the Chinese government, and who could blame them?

> Please direct me to the federal programs which are actively pursuing the above.

Did you yet read any of the links I gave? Walt, I only do homework help with a note from a teacher. You’ve been doing the “nobody but me knows what to do next” routine for many days here and never once commented on any of the things people have pointed to that are already accomplishing the things you seem to think you’re suggesting for the first time. You can look this stuff up if you bother. Then critique the efforts, don’t claim there’s nobody but you who imagines the need for such programs.

One suggestion: Google: transformer energy efficiency DOE lawsuit

Google (and Scholar) each of the suggestions you’ve made. Read what’s being done.
Comment on what’s being done and how it can be improved. You might have a good idea.

906: Gavin said “where did that come from” It came from me misreading. Sorry. We’re not below 1991 levels. 2008 was down 2.8% from 2007 and 2009 was down 6% from 2008, but as Gavin said we’re well above 1991 levels. The 2009 level will rise this year. Still I stand by my prediction that we’ll have 100GW of wind power capacity by the end of 2015. If that works out I still think we have a decent chance to be done with coal by 2050.

“As you surely know, there are many reservoirs which are not the result of dams.”

I’m just a simple fisheries biologist who surveyed a vast area of western national forest watersheds over the last 20 years, but where I come from in Maine, we call those lakes. Are you saying we should dig more lakes? Try to stay in your field, Walt, which according to your blog is avoiding taxes. It sure as hell isn’t watershed science or any other scientific discipline.

We agree that energy efficiency slays more than one dragon, and that there is some low-hanging fruit.

We agree that there are some good ideas out there which unfortunately encounter a lot of resistance.

Now, some things I submit that we could agree on:

There is no national commitment to specific targets for energy effiency.

There is no coordinated national effort to plan for the eventual likely effects of persistent warming.

I won’t ask you to agree with me regarding what time it is; I’ve made my argument, I can provide supporting documentation, we all have to decide what the information means to us.

But my issue is this, sir: My “good idea” is to get us to a point where enough of us agree on what constitutes a “good idea” that we have a chance to get it done.

I see no point in continuing to attempt this on an international scale. It amounts to fiddling while Rome burns. Rome is going to burn anyway, so we have to learn to live with the consequences.

I do not dispute that you can find anecdotal evidence of good-faith efforts to accomplish some of these “green goals”. I would simply ask you to compare that with the ticking clock of AGW. I assume that you are at least as familiar with the science as I am, therefore you know about acceleration and some of what Hansen has said about it. You understand that CO2 will continue to rise, as will temperature, even after man stops adding to the atmospheric levels. You know it will be many decades, no matter how successful we are at reducing CO2 emissions, before AGW “turns around”, and I presume you know that the likelihood is that the even must complete before that can happen.

Last one for Walt B: Sorry if you object to my attribution of “rants” to you. I was using it good-humoredly. And, considering the number and volume of your comments, I thought accurately. I will desist.

I skimmed rather fast over the weekend’s prose, but you were kind enough to pin down the bases of our disagreements at 12 February 2010 at 1:56 PM, with your statement that

“If we are to believe the science, destabilization is already underway and are past the tipping point to prevent further destabilization.”

This statement is unsupported to the point of utterly fatal weakness. It is grossly vague, and can’t have much force until tightened up, expanded upon, and so solidly supported in the peer-reviewed literature that there is hardly any oppostion. You can’t even come within shouting distance of doing that. Don’t even try. You’d have to write (or rather, respected authorities would have to write) an IPCC-style and IPCC-length review to make most of us believe that. Gimme a break. Preposterous, for at least the next several decades, and maybe for centuries. Making pessimistic statements out of your own predilections is one thing, but reading them is getting boring. My engagement with you is over until you contribute a new thought. Have the last word if you wish, be my guest.

We would have to have a longer discussion about what that sentence implies.

To me it implies that we just haven’t tried hard enough to convince people, that somehow the effort is lacking.

But do you honestly believe that?

I don’t know how long you’ve been involved in the “AGW debate”. For me it’s not that long, 3+ years, but in just that time I’ve had an incredible arc in my reaction to denialist positions.

At first I thought they were just confused. That didn’t last long. I soon found out that they were dug in and that they had some prominent scientists on their side. Warmists were already quite busy attempting to undermine the validity of these scientists.

I’ll gloss over the back and forth; presumably you are quite familiar with it yourself.

Unfortunately, one inescapable conclusion I have reached at this point is that the denialist position is highly adaptable and probably undefeatable, for several reasons:

1. AGW takes a long, long time to kick into a gear that will stir a conscious response;

2. Annual variability means that we will, on a regular basis have unusual “cold” events, which will serve to undermine the message;

3. AGW science is of course a pursuit of knowledge which will never be complete; the denialist camp has become expert at turning this uncertainty and replacing of older information with new into spin which declares: “They just don’t know, and they’re asking us to bet the future on it.”

To that last point you would probably say: “It’s the uncertainty that makes it important to act as soon as possible.”

Which they bat down dismissively. There are more important short term problems to deal with, they say.

The point being: A large chunk of the public responds positively to those messages.

And keep in mind: A lot of people just don’t trust the government. I could give you solid reasons why Dr. Hansens’ favored approach, fee/rebate, could almost certainly never happen in the U.S. Short version: It would be seen by some as another massive government program. There is enough resistance to such things in American politics to, at minimum, stall it for the foreseeable future.

The denialist intent has been to stall. Stalling has always been the enemy of nipping this in the bud.

And that’s where we are, I think you’d have to agree.

By now you know why I stand where I do. I take it that you still disagree, and I have accepted the responsibility to develop my position more thoroughly.

When I have that done I will post it online and let you and others know where to find it.

I don’t want anybody to think that I am simply making wild accusations in order to be “different”.

Nothing could be less true. I had to be pried off of the AGW bandwagon, and it was the evidence that finally did it.

Certainly some of us are screwed. That’s inescapable. There will be disruption. It will mostly be slow, but specific events will lead to mass displacements.

By “slow” I mean: slow enough to adapt to.

But I absolutely do not believe that we are all screwed. I believe there will be survivors, and those people will be highly adaptable. Of course there will be massive loss of life in the interim, not purely from climate but from the wars which will no doubt be necessary to prune the human herd enough to survive on the remaining resources.

But then what will happen? The tundra of the north will prove habitable, opening up new land for development and cultivation. What is now white, then brown will eventually be green, and become a net CO2 sink. Man will be “reborn” after his near-death.

None of it avoidable. If it wasn’t climate change it would be overpopulation, or religious intolerance, or two nations mad enough to hurl nukes at each other.

I believe that recent scientific observations are clear that ice mass loss is accelerating rapidly. There is a certain amount of energy implied in that process. It would take a certain amount of energy to reverse that process. It does not need much more external energy in order to complete itself.

I believe that much of the above can be quantified based on recent observations and assessments.

I also believe there are many previous efforts to determine how ice sheets break up, including by Dr. Hansen, which predicted as much: The process will start slow and pick up speed; past a certain point, the event must complete itself (notwithstanding an enormous offsetting force, which is absolutely unimaginable).

I absolutely believe that a strong case can be made that the acceleration can no longer be stopped.

Ric’s somewhat ad-hom, informationless comment did accomplish one thing that can be put to use:

We get to look at how warmists like to have it both ways.

Ric says that we need to “prove” that we are past the tipping point for unstoppable acceleration of ice mass loss. In other words, visual evidence, something undeniable. He refuses to accept acceleration any other way.

And yet, what about AGW itself? We are told, over and over, that by the time we “see” proof it will be too late to stop it. Ric has no trouble accepting that premise on faith. He accepts, as do I, that waiting until we see and feel the effects at such a level that it is no longer deniable, will be far too late.

Yet he demands visual proof that we are past the tipping point. In this regard, solid science is not enough. In this regard, there is all sorts of room for doubt.

SO, what we’re certain of and uncertain of would seem to depend on what preconceived outcome we prefer.

BPL: How do you adapt to a sudden drastic cut in the amount of available food?

Will some people survive the collapse? Sure. But our civilization won’t. I like civilization. I like electricity, warm houses, and indoor plumbing. I like computers and the internet. I like books. I like being able to buy food when I have the money to do so. I don’t want to lose any of those things. The consequences of doing so are not trivial.

WB: Of course there will be massive loss of life in the interim, not purely from climate but from the wars which will no doubt be necessary to prune the human herd enough to survive on the remaining resources.

BPL: What makes you think you’ll be among the survivors and not those who get pruned?